World Rugby defends smart mouthguards amid rising criticism

George Turner - World Rugby defends smart mouthguards amid rising criticism
Scotland hooker George Turner became the first player in the Six Nations to be forced off the field by his "smart mouthguard" - Getty Images/Ross Parker

World Rugby has defended the newly-introduced smart mouthguard system following criticism in the Six Nations and Super Rugby after incidents over the weekend.

Scotland have seen George Turner and Zander Fagerson removed from play in successive matches for head injury assessments which were triggered by alerts from the new mouthguards, which led to head coach Gregor Townsend expressing caution over “trusting technology that has not been proven” in the aftermath of his side’s win over England.

Scott Barrett, the Crusaders and New Zealand lock, described the technology as “a step too far” after two players were removed following alerts in Friday’s Super Rugby opener between the Chiefs and the Crusaders.

World Rugby said seven players have been removed following mouthguard alerts for head injury assessments so far during the Six Nations. The new mouthguards measure high acceleration events, using an accelerometer and gyroscope, with any impact above 70g and 4,000 radians per second squared in the men’s game – higher than the forces sustained by Formula One drivers in some recent crashes, such as Romain Grosjean in 2020 – leading to an HIA.

Lindsay Starling, World Rugby’s science and medical manager, explained the seven incidents leading to HIAs were part of 9,500 monitored head accelerations in the Six Nations so far.

“Past this [threshold], the players are sustaining really big impacts. They are in the top 0.1 per cent of impact events” said Starling.

“We see this as a real game-changer. It enables us to understand information about the players that we have never known before and cannot know just from observing.

“We’ve known for the last decade-plus that concussion is a topic that requires a huge amount of attention. Over the last few years that narrative has changed slightly to encompass all head-impact events, all head-acceleration events, not just those that manifest in clinical symptoms such as concussion.”

“That is to put it into perspective regarding how rare and small these numbers are in terms of the players coming off. For a player to be removed, it means they have sustained a really big knock.

“We are confident in the data that comes from the mouthguards and confident in the technology. We wouldn’t be introducing this on such a large scale if we weren’t confident in the data that is coming from them.

“From research we’ve done over the last few years, we have essentially identified a threshold whereby any impact that is occurring to a player above that threshold, it is very likely that the player displays signs of clinical concussion.”

In Super Rugby the All Blacks centre Anton Lienert-Brown was removed in the final minutes of the Chiefs’ win over the Crusaders, appearing visibly frustrated at having to leave the field with the game on the line.

Lienert-Brown has since backed the innovation. “This technology’s here for our best interests and that’s definitely something I don’t want to knock,” he said on Tuesday.

It has emerged his withdrawal was in fact related to an earlier collision in the match, with a delayed message between the mouthguard and the “responder” due to connection issues causing the confusion; a problem which has since been addressed.

Responders in the Six Nations are worn by referees and are therefore closer to the action, although there was a delay of over four minutes between the collision which led to Turner’s HIA alert – triggered when the hooker made a tackle on France’s Charles Ollivon – and when Turner was actually removed from the field. He later returned and played into the second half, as Fagerson did against England.